carb seems to flood itself out (whenever it feels like it)- front bowl overflows. carb is stock 780 holley- any ideas on curing problem, and if new needle is needed, where is good place to purchase correct one?

Yes, the 1st thing I'd check is the front needle and seat. You could have a piece of trash in it, or it could be worn out. It also could be the front float. I had one years ago that gave me "fits". The carb would flood sometimes when it got warmed up. Come to find out, the float had a pin-hole in it, that would expand with heat. The float would fill with gas and "sink". Definitely worth ckecking.